Volume 14 Kuinber tj 



The Plant World 



A Magazine oK Geni:rai, Botany 

 JUNE, 1911 



CLBLVTIC Sl'LlvCTlOX IX A PIVHRID PROGKXY. 



D. T. MAcDoroAi,. 



A number of acorns of Ouercus luicyof^Jijl/d were secured 

 from some trees on Staten Island, X. \., in October, LS95, 

 and germinated in the Xew York Botanical Gardens a few 

 weeks later. The cidtures were made for testing the character 

 of the living material grouped under this name by systema- 

 tists, and with especial reference to the probable parents in 

 case evidences of hybrid origin were found. '•' 



The 55 plantlets obtained were seen to vary widelv from 

 each other as to leaf form, although the range of variation on any 

 one plant was small. By the close of 1906 it was seen that 

 the entire lot might be arranged in a linear series, in which 

 the ])lants at one end i^ore broad lobed leaves much like those of 

 the red oak, while the individuals at the other extreme resembled 

 the willow-leaved oak {Oiicrcus Phellos). This fact was taken 

 as evidence strongly sup])orting the conclusions of Dr. A. A. 

 llollick and other bolantists that 0. hcicrophylla was a hybrid 

 between the red oak (0. rubra) and the willow leaved oak((_>. 

 Phellos). 



I'lants representing the suj^poscd h\ brid species have been 

 known for a long lime, so that nothing might be said as to the 

 relationshi]) of the plantlets grown and the original cross. The 

 parental trees from which the acorns were taken might have 

 been first generation crosses, or on the other hand they ma\' 

 have represented the nXh generation with many possibilities 



♦ MacDougal, Hybridizatioii of Wild Plants. Bot. Gaz.. 43: 11. 1907. 



